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Abstract Background Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors, with high incidence and poor prognosis. Revealing mechanisms of ESCC progression and developing new therapeutic targets remains crucial. The aim of this study was to elucidate the molecular mechanism of miR‐30c‐5p in regulating the malignant progression of ESCC. Methods TCGA, GEO, and other datasets were used to analyze the differential expression of miR‐30c‐5p in ESCC and adjacent tissues, and its impact on prognosis. Then the effects of miR‐30c‐5p on the proliferation, migration, and invasion of TE‐1 and Eca9706 cells were investigated through proliferation experiments, transwell and wounding healing assays. The regulatory mechanism of miR‐30c‐5p on the PI3K/AKT signaling pathway and its interaction in cancer progression were investigated through Western blots, dual‐luciferase reporter assay, and rescue experiments. Results miR‐30c‐5p was significantly downregulated in ESCC tissue and represented a poor prognosis. miR‐30c‐5p mimic significantly inhibited the proliferation, migration, and invasion ability of ESCC, while miR‐30c‐5p inhibitor significantly promoted tumor cell progression. Through bioinformatic analysis and experimental results, miR‐30c‐5p interacted directly with PIK3CA mRNA and inhibited subsequent signaling pathway activation. PIK3CA activator could eliminate the inhibitory effects of miR‐30c‐5p mimic on the progression of ESCC, while PIK3CA inhibitors could rescue the promoting effect of miR‐30c‐5p inhibitor group cells. Conclusions In summary, we found that miR‐30c‐5p inhibited the proliferation, invasion and migration of ESCC by inhibiting PI3K/AKT signaling pathway for the first time, and this study is expected to provide a novel insight and potential therapeutic target for managing ESCC.

Abstract Neutrophil extracellular traps (NETs) have been implicated in the pathology of various inflammatory conditions. In cancer, NETs have been demonstrated to induce systemic inflammation, impair peripheral vessel and organ function and promote metastasis. Here we show that the plasma level of NETs is significantly higher in patients with metastatic breast cancer compared to those with local disease, or those that were considered cured at a 5‐year follow‐up, confirming NETs as interesting therapeutic targets in metastatic breast cancer. Administration of DNase I is one strategy to eliminate NETs but long‐term treatment requires repeated injections and species‐specific versions of the enzyme. To enhance administration and therapeutic efficacy, we have developed an adeno‐associated virus (AAV) vector system for delivery of murine DNase I and addressed its potential to counteract cancer‐associated pathology in the murine MMTV‐PyMT model for metastatic mammary carcinoma. The AAV vector is comprised of capsid KP1 and an expression cassette encoding hyperactive murine DNase I (AAV‐mDNase I) under the control of a liver‐specific promotor. This AAV‐mDNase I vector could support elevated expression and serum activity of murine DNase I over at least 8 months. Neutrophil Gelatinase‐Associated Lipocalin (NGAL), a biomarker for kidney hypoperfusion that is upregulated in urine from MMTV‐PyMT mice, was suppressed in mice receiving AAV‐mDNase I compared to an AAV‐null control group. Furthermore, the proportion of mice that developed lung metastasis was reduced in the AAV‐mDNase I group. Altogether, our data indicate that AAV‐mDNase I has the potential to reduce cancer‐associated impairment of renal function and development of metastasis. We conclude that AAV‐mDNase I could represent a promising therapeutic strategy in metastatic breast cancer.

Abstract Background Lung cancer is one of the major threats to human life worldwide. MiR‐190 has been found to perform essential roles in multiple cancer progression; however, there have been no studies focused on its function and underlying regulatory mechanism in lung cancer. Method The miR‐190 expression was detected by real‐time quantitative polymerase chain reaction (RT‐qPCR). The cell functional experiments, including cell counting kit‐8 (CCK‐8), colony formation and transwell assay were conducted in vitro, as well as animal experiments performed in vivo. The regulation and potential binding sites of CBX4 on miR‐190 were predicted by TCGA data set and JASPAR website and verified by ChIP assay and dual‐luciferase reporter assay. The prospects binding site of miR‐190‐3p on CBX4 3′UTR region was predicted by StarBase and verified by dual‐luciferase reporter assay. Results MiR‐190 was decreased in lung cancer cells. The overexpression of miR‐190 had no effects on cell proliferation, but significantly inhibited cancer metastasis both in vitro and in vivo. Moreover, miR‐190 expression could be transcriptionally inhibited by CBX4, and CBX4 was the direct target of miR‐190‐3p. Conclusion MiR‐190 served as a cancer metastasis inhibitor in lung cancer and formed a regulatory loop with CBX4. These findings provided emerging insights into therapeutic targets and strategies for metastatic lung cancer.

Abstract Prostate cancer (PCa) metastasis significantly influences treatment decisions and prognosis. This study evaluated the individual and combined diagnostic ability of apparent diffusion coefficient (ADC), Gleason score and prostate‐specific antigen (PSA) in detecting metastasis. The study included data from 120 biopsy‐confirmed PCa patients treated from 2019 to 2023. Whole‐body MRI images, incorporating high‐resolution T2 and axial DWI sequences, were evaluated by experienced radiologists. Receiver operating characteristic (ROC) curves and logistic regression models were used to assess the diagnostic performance of ADC, Gleason score, and PSA in detecting metastasis. The prevalence of PCa metastasis was 25.0%, with pelvic lymph node metastasis (16.7%) and bony metastasis (12.5%) being most prevalent. Patients with PCa metastasis had significantly lower ADC values, higher Gleason scores, and higher PSA levels compared to those without metastasis. Individually, an ADC cut‐off of ≤549.00 mm2/s was the best marker for detecting metastasis. The combined bioscore model including PSA, ADC values and Gleason score was the best independent predictor, correlating with a 159‐fold increased likelihood of detecting PCa metastasis. This study demonstrated the prognostic ability of PCa markers in detecting metastasis. ADC was an independent, sensitive, specific, and accurate diagnostic marker. The combined bioscore model of ADC, PSA and Gleason score significantly enhanced the identification of patients with PCa metastasis.

Abstract Media supplemented with sera from acutely exercised men has been shown to have ‘anti‐cancer’ effects on prostate and breast cancer cell lines. This study investigated whether media supplemented with plasma samples taken at rest (≥30 h since the most recent exercise session) from men who were endurance‐trained (END), strength‐trained (STR) or recreationally active controls (CON) impacted the results of four assays that mimic hallmarks of cancer (proliferation, migration, extracellular matrix invasion and anoikis resistance) in the BT‐549 breast cancer cell line. Compared to control conditions of either serum‐free media or fetal bovine serum as appropriate, BT‐549 cells cultured with plasma‐supplemented media regardless of group resulted in greater cell proliferation (∼20–50%) and cell migration (∼15–20%), and lower extracellular matrix invasion (∼10–20%) and anoikis resistance (∼15–20%). Supplementing media with plasma from END or STR did not impact any outcomes of these assays compared to plasma from CON. Media supplemented with human plasma can impact functional assays reflective of cancer hallmarks in BT‐549 cells, but effects of exercise on proliferation, migration, extracellular matrix invasion and anoikis resistance were not evident in resting blood samples of individuals with a prior history of exercise training.

Abstract By presenting the most up‐to‐date findings and incorporating the latest evidence, this article seeks to present a comprehensive guide for navigating the complexities inherent in the management of colorectal liver metastasis. It aims to serve as a valuable resource offering clinicians and healthcare professionals an understanding of the diverse modalities and approaches available for treating this challenging and multifaceted disease. In an era of rapidly evolving medical knowledge, this article examines the latest insights to make informed decisions in the realm of colorectal liver metastasis management. The article does not only highlight the up‐to‐date knowledge but also provides the evidence for existing therapeutic strategies. This practical tool provides evidence‐based recommendations to clinicians, thereby contributing to the ongoing advancement of effective treatment strategies for this challenging disease.

Clear cell renal cell carcinoma (ccRCC) accounts for approximately 75–80% of all patients with renal cell carcinoma. Despite its prevalence, little is known regarding the key components involved in ccRCC metastasis. In this study, scRNA‐seq analysis was employed to classify CD8+ T cells into four sub‐clusters based on their genetic profiles and immunofluorescence experiments were used to validate two key clusters. Through gene set enrichment analysis, these newly identified sub‐clusters were found to exhibit distinct biological characteristics. Notably, TYMP, TOP2A, CHI3L2, CDKN3, CENPM, and RZH2 were highly expressed in these sub‐clusters, indicating a correlation with poor prognosis. Among these sub‐clusters, CD8+ T cells (MT‐ND4) were identified as potentially playing a critical role in mediating ccRCC metastasis. These results contribute to our understanding of CD8+ T cell heterogeneity in ccRCC and shed light on the mechanisms underlying the loss of immune response against cancer.

ABSTRACT Background Small cell lung cancer (SCLC) harbours the most aggressive phenotype of all lung cancers to correlate with its bleak prognosis. The aggression of SCLC is partially attributable to its strong metastatic tendencies. The biological processes facilitating the metastasis in SCLC are still poorly understood and garnering a deeper understanding of these processes may enable the exploration of additional targets against this cancer hallmark in the treatment of SCLC. Recent Findings This narrative review will discuss the proposed molecular mechanisms by which the cancer hallmark of activating invasion and metastasis is featured in SCLC through important steps of the metastatic pathway, and address the various molecular targets that may be considered for therapeutic intervention. The tumour immune microenvironment plays an important role in facilitating immunotherapy resistance, whilst the poor infiltration of natural killer cells in particular fosters a pro‐metastatic environment in SCLC. SCLC vasculogenesis is achieved through VEGF expression and vascular mimicry, and epithelial‐mesenchymal transition is facilitated by the expression of the transcriptional repressors of E‐cadherin, the suppression of the Notch signalling pathway and tumour heterogeneity. Nuclear factor I/B, selectin and B1 integrin hold important roles in SCLC migration, whilst various molecular markers are expressed by SCLC to assist organ‐specific homing during metastasis. The review will also discuss a recent article observing miR‐1 mRNA upregulation as a potential therapeutic option in targeting the metastatic activity of SCLC. Conclusion Treatment of SCLC remains a clinical challenge due to its recalcitrant and aggressive nature. Amongst the many hallmarks used by SCLC to enable its aggressive behaviour, that of its ability to invade surrounding tissue and metastasise is particularly notable and understanding the molecular mechanisms in SCLC metastasis can identify therapeutic targets to attenuate SCLC aggression and improve mortality.

ABSTRACT Background Medullary thyroid cancer (MTC) is one of the rare neuroendocrine malignancies. This cancer is hereditary in approximately 20% of cases. Although lymph node (LN) metastasis is prevalent in MTC, distant metastasis is not commonly seen in these patients. The most common locations for metastasis are the lungs, liver, and bones. This study presents an extremely rare MTC metastasis to bone marrow (BM) and adrenal gland, which has not been reported before. Case The patient was a 50‐year‐old man with a diagnosis of MTC and total thyroidectomy 2 months before his presentation. He came to the emergency department (ED) complaining of dyspnea, diffuse bone pain, nonbloody diarrhea, and abdominal cramps starting in the last month before. Initial treatment with intravenous fluid infusion and loperamide, due to the provisional diagnosis of infectious diarrhea, was ineffective. Further assessments revealed severe pancytopenia and a massive tumor above the left kidney. Bone marrow aspiration (BMA) and biopsy (BMB) led to the diagnosis of invasive metastasis of the MTC to the BM and the left adrenal gland. In the initial evaluations, his COVID‐19 test became positive, and despite all efforts, his condition deteriorated, and he died 5 days after admission due to respiratory distress. Conclusion Most MTC cases present with thyroid nodules in the initial steps and are confined to the thyroid gland or the adjacent LNs. These cases are mostly cured by thyroidectomy and LN dissection. This neuroendocrine cancer infrequently becomes aggressive and involves other parts of the body. However, involving BM or adrenal gland has been scarcely reported. Due to ineffective red and white blood cell production, BM metastasis can cause pancytopenia and, consequently, pallor, fatigue, dyspnea, and susceptibility to infections. High calcitonin levels can also cause diarrhea. The initial diagnosis is mostly with neck ultrasound (US) and fine needle aspiration (FNA). Total thyroidectomy is the main therapeutic option for these patients. Calcitonin and carcinoembryonic antigen (CEA) are sensitive indicators of recurrence or remaining tumors, which might be helpful for the initial diagnosis and postoperation follow‐up. Although extremely rare, invasive metastasis of MTC might involve unusual body organs such as the BM or adrenal glands. In cases of unjustifiable pancytopenia or adrenal dysfunction in MTC‐positive patients, these possibilities should be considered and ruled out by some specific evaluations, such as bone marrow biopsy and contrast‐enhanced imaging.

Abstract Lipid metabolism reprogramming stands as a fundamental hallmark of cancer cells. Unraveling the core regulators of lipid biosynthesis holds the potential to find promising therapeutic targets in pancreatic ductal adenocarcinoma (PDAC). Here, it is demonstrated that platelet‐derived growth factor C (PDGFC) orchestrated lipid metabolism, thereby facilitated the malignant progression of PDAC. Expression of PDGFC is upregulated in PDAC cohorts and is corelated with a poor prognosis. Aberrantly high expression of PDGFC promoted proliferation and metastasis of PDAC both in vitro and in vivo. Mechanistically, PDGFC accelerated the malignant progression of PDAC by upregulating fatty acid accumulation through sterol regulatory element‐binding protein 1 (SREBP1), a key transcription factor in lipid metabolism. Remarkably, Betulin, an inhibitor of SREBP1, demonstrated the capability to inhibit proliferation and metastasis of PDAC cell lines, along with attenuating the process of liver metastasis in vivo. Overall, the study underscores the pivotal role of PDGFC‐mediated lipid metabolism in PDAC progression, suggesting PDGFC as a potential biomarker for PDAC metastasis. Targeting PDGFC‐induced lipid metabolism emerges as a promising therapeutic strategy for metastatic PDAC, with the potential to improve clinical outcomes.

Abstract Objective To investigate primary site surgical resection and overall survival (OS) in clinically distantly metastatic (cM1) oral cavity squamous cell carcinoma (OCSCC). Methods The 2006–2018 National Cancer Database was queried for patients presenting with cM1 OCSCC who underwent chemotherapy. Binary logistic, Kaplan–Meier, and multivariable Cox proportional hazards regression models were implemented. Results Of 278 patients satisfying inclusion criteria, 139 (50.0%) underwent chemotherapy alone, 80 (28.8%) underwent chemoradiotherapy, 25 (9.0%) underwent surgical resection + adjuvant chemotherapy, and 34 (12.2%) underwent surgical resection + adjuvant chemoradiotherapy; 5‐year OS was 9.4%, 15.2%, 8.3%, and 23.8%, respectively (p

Key Clinical Message Isolated gastric outlet obstruction secondary to breast carcinoma is a rare and often challenging diagnosis. Clinicians must be cognizant of this diagnosis even in cases where breast cancers have been in remission alongside more common causes of mechanical obstruction including pancreatic and gastric carcinomas and peptic ulcer disease.

Abstract Cancer stem cells (CSCs) are widely acknowledged as the drivers of tumor initiation, epithelial‐mesenchymal transition (EMT) progression, and metastasis. Originating from both hematologic and solid malignancies, CSCs exhibit quiescence, pluripotency, and self‐renewal akin to normal stem cells, thus orchestrating tumor heterogeneity and growth. Through a dynamic interplay with the tumor microenvironment (TME) and intricate signaling cascades, CSCs undergo transitions from differentiated cancer cells, culminating in therapy resistance and disease recurrence. This review undertakes an in‐depth analysis of the multifaceted mechanisms underlying cancer stemness and CSC‐mediated resistance to therapy. Intrinsic factors encompassing the TME, hypoxic conditions, and oxidative stress, alongside extrinsic processes such as drug efflux mechanisms, collectively contribute to therapeutic resistance. An exploration into key signaling pathways, including JAK/STAT, WNT, NOTCH, and HEDGEHOG, sheds light on their pivotal roles in sustaining CSCs phenotypes. Insights gleaned from preclinical and clinical studies hold promise in refining drug discovery efforts and optimizing therapeutic interventions, especially chimeric antigen receptor (CAR)‐T cell therapy, cytokine‐induced killer (CIK) cell therapy, natural killer (NK) cell‐mediated CSC‐targeting and others. Ultimately use of cell sorting and single cell sequencing approaches for elucidating the fundamental characteristics and resistance mechanisms inherent in CSCs will enhance our comprehension of CSC and intratumor heterogeneity, which ultimately would inform about tailored and personalized interventions.

Abstract Background Previous studies have demonstrated that the glycolytic enzyme phosphoglycerate kinase 1 (PGK1) can promote tumor development. This study sought to investigate the specific role of PGK1 in bladder cancer (BLCA). Methods Public databases and immunohistochemistry assays were utilized to analyze the expression of PGK1 in BLCA and its prognostic significance. Cell proliferation was assessed through CCK‐8 and colony formation assays, while the level of metastasis was evaluated using transwell migration experiments. Additionally, IC50 experiments were conducted to assess the impact of PGK1 on cisplatin sensitivity. Results The mRNA and protein expression levels of PGK1 were significantly upregulated in BLCA. Cox proportional hazards model analysis revealed that PGK1 and T stage were independent prognostic factors for BLCA patients. Both CCK‐8 and colony assays demonstrated that PGK1 promotes proliferation. Furthermore, a positive correlation was observed between PGK1 and Ki67, a proliferation index. Transwell migration assays confirmed the ability of PGK1 to enhance metastasis. Finally, PGK1 increased the IC50 associated with cisplatin treatment in BLCA. Conclusion Collectively, these findings suggest that PGK1 may hold clinical value in predicting BLCA prognosis and improving the outcomes of this patient population.

Abstract Transmembrane protein 52B (TMEM52B), a newly identified tumor‐related gene, has been reported to regulate various tumors, yet its role in nasopharyngeal carcinoma (NPC) remains unclear. Transcriptomic analysis of NPC cell lines reveals frequent overexpression of TMEM52B, and immunohistochemical results show that TMEM52B is associated with advanced tumor stage, recurrence, and decreased survival time. Depleting TMEM52B inhibits the proliferation, migration, invasion, and oncogenesis of NPC cells in vivo. TMEM52B encodes two isoforms, TMEM52B‐P18 and TMEM52B‐P20, differing in their N‐terminals. While both isoforms exhibit similar pro‐oncogenic roles and contribute to drug resistance in NPC, TMEM52B‐P20 differentially promotes metastasis. This functional discrepancy may be attributed to their distinct subcellular localization; TMEM52B‐P18 is confined to the cytoplasm, while TMEM52B‐P20 is found both at the cell membrane and in the cytoplasm. Mechanistically, cytoplasmic TMEM52B enhances AKT phosphorylation by interacting with phosphoglycerate kinase 1 (PGK1), fostering NPC growth and metastasis. Meanwhile, membrane‐localized TMEM52B‐P20 promotes E‐cadherin ubiquitination and degradation by facilitating its interaction with the E3 ubiquitin ligase NEDD4, further driving NPC metastasis. In conclusion, the TMEM52B‐P18 and TMEM52B‐P20 isoforms promote the metastasis of NPC cells through different mechanisms. Drugs targeting these TMEM52B isoforms may offer therapeutic benefits to cancer patients with varying degrees of metastasis.

Abstract Reactive oxygen species (ROS)‐induced oxidative DNA damages have been considered the main cause of mutations in genes, which are highly related to carcinogenesis and tumour progression. Extracellular vesicles play an important role in cancer metastasis. However, the precise role of DNA oxidative damage in extracellular vesicles (EVs)‐mediated cancer cell migration and invasion remains unclear. Here, we reveal that ROS‐mediated DNA oxidative damage signalling promotes tumour metastasis through increasing EVs release. Mechanistically, 8‐oxoguanine DNA glycosylase (OGG1) recognises and binds to its substrate 8‐oxo‐7,8‐dihydroguanine (8‐oxoG), recruiting NF‐κB to the synaptotagmin 7 (SYT7) promoter and thereby triggering SYT7 transcription. The upregulation of SYT7 expression leads to increased release of E‐cadherin‐loaded EVs, which depletes intracellular E‐cadherin, thereby inducing epithelial‐mesenchymal transition (EMT). Notably, Th5487, the inhibitor of DNA binding activity of OGG1, blocks the recognition and transmission of oxidative signals, alleviates SYT7 expression and suppresses EVs release, thereby preventing tumour progression in vitro and in vivo. Collectively, our study illuminates the significance of 8‐oxoG/OGG1/SYT7 axis‐driven EVs release in oxidative stress‐induced tumour metastasis. These findings provide a deeper understanding of the molecular basis of cancer progression and offer potential avenues for therapeutic intervention.

Abstract Nasopharyngeal carcinoma (NPC), a squamous cell carcinoma originating in the nasopharynx, is a leading malignancy in south China and other south and east Asia areas. It is frequently associated with Epstein‐Barr virus (EBV) infection, while there are also some NPC patients without EBV infection. Here, it is shown that the EBV+ (EBV positive) and EBV‐ (EBV negative) NPCs contain both shared and distinct genetic abnormalities, among the latter are increased mutations in TP53. To investigate the functional roles of NPC‐associated genetic alterations, primary, orthotopic, and genetically defined NPC models were developed in mice, a key tool missed in the field. These models, initiated with gene‐edited organoids of normal nasopharyngeal epithelium, faithfully recapitulated the pathological features of human disease. With these models, it is found that Trp53 and Cdkn2a deficiency are crucial for NPC initiation and progression. And latent membrane protein1 (LMP1), an EBV‐coding oncoprotein, significantly promoted the distal metastasis. Further, loss of TGFBR2, which is frequently disrupted both in EBV‐ and EBV+ NPCs, dramatically accelerated the progression and lung metastasis of NPC probably by altering tumor microenvironment. Taken together, this work establishes a platform to dissect the genetic mechanisms underlying NPC pathogenesis and might be of value for future translational studies.

Abstract Frequent recurrence and metastasis caused by cancer stem cells (CSCs) are major challenges in lung cancer treatment. Therefore, identifying and characterizing specific CSC targets are crucial for the success of prospective targeted therapies. In this study, it is found that upregulated TOR Signaling Pathway Regulator‐Like (TIPRL) in lung CSCs causes sustained activation of the calcium/calmodulin‐dependent protein kinase kinase 2 (CaMKK2) signaling pathway by binding to CaMKK2, thereby maintaining stemness and survival. CaMKK2‐mediated activation of CaM kinase 4 (CaMK4) leads to phosphorylation of cAMP response element‐binding protein (CREB) at Ser129 and Ser133, which is necessary for its maximum activation and the downstream constitutive expression of its target genes (Bcl2 and HMG20A). TIPRL depletion sensitizes lung CSCs to afatinib‐induced cell death and reduces distal metastasis of lung cancer in vivo. It is determined that CREB activates the transcription of TIPRL in lung CSCs. The positive feedback loop consisting of CREB and TIPRL induces the sustained activation of the CaMKK2‐CaMK4‐CREB axis as a driving force and upregulates the expression of stemness‐ and survival‐related genes, promoting tumorigenesis in patients with lung cancer. Thus, TIPRL and the CaMKK2 signaling axis may be promising targets for overcoming drug resistance and reducing metastasis in lung cancer.

Key Clinical Message Hepatocellular carcinoma (HCC) is one of the most common types of cancer. More focus is being placed on clinical presentations of distant metastasis from HCC. Head masses should be investigated even when no concerning symptoms are found in patients with prior history of alcohol abuse and liver comorbidities.

Key Clinical Message Epicardial metastasis from mixed germ cell tumors is exceedingly rare and poses a significant risk for cardiac morbidity. This case highlights the crucial need for comprehensive systemic evaluation in patients with known malignancies presenting with cardiac symptoms.

Abstract Background Colorectal cancer (CRC) is a prevalent and lethal tumor, with metastasis being the leading cause of mortality. Previous research has indicated that the long non‐coding RNA (lncRNA) CCAT2 is involved in the regulation of various tumor progression mechanisms. However, the precise role of CCAT2 in CRC proliferation and metastasis remains ambiguous. This study seeks to elucidate the mechanisms through which CCAT2 influences CRC. Methods High‐throughput sequencing and RT‐qPCR were used to detect CCAT2 expression in CRC. Functional analyses including CCK8, colony formation, wound healing migration, transwell chamber, and Muse® Cell Analyzer assays were performed to study the effects of CCAT2 gene deletion on CRC cells. RNA‐pulldown and protein mass spectrometry were employed to identify the interaction between CCAT2 and GNB2 protein. Results Increased CCAT2 expression was found in CRC, especially in metastatic CRC. Deletion of CCAT2 gene inhibited CRC cell proliferation, migration, and invasion while promoting apoptosis. The interaction between CCAT2 and GNB2 protein was shown to modulate GNB2 protein alterations and affect the ERK and Wnt signaling pathways, thereby promoting CRC proliferation and metastasis. Conclusion CCAT2 plays a crucial role in CRC progression by modulating the ERK and Wnt signaling pathways through its interaction with GNB2. These findings highlight the importance of CCAT2 as a key regulatory element in the mechanisms underlying CRC proliferation and metastasis.

Abstract Objective The TGF‐β superfamily member activin, a dimer of the gene products of INHBA and/or INHBB, has been implicated in immune cell maturation and recruitment, but its immune impact within epithelial ovarian cancer (EOC) is not well characterized. We sought to explore differences in activin (INHBA/ Inhibin‐βA and INHBB/ Inhibin‐βB) between malignant and ovarian tissues at the RNA and protein level and assess the relationship between activin and immune cells in EOC. Methods Publicly available RNA sequencing data were accessed from GEO (#GSE143897) with normalization and quantification performed via DESeq2. Immune gene expression profile was further explored within the TCGA‐OV cohort derived from The Cancer Genome Atlas (TCGA). Immunohistochemical analysis was performed to evaluate activin A and T‐cell markers CD8 and FoxP3 at the protein level. ELISA to activin‐A was used to assess levels in the ascites of advanced EOC patients. Kaplan–Meier curves were generated to visualize survival outcomes. Results Gene expression levels of components of the activin signaling pathway were elevated within EOC when compared to a benign cohort, with differences in activin type I/II receptor gene profiles identified. Additionally, INHBA gene expression was linked to lymphocytic immune markers in EOC samples. Immunohistochemistry analysis revealed a positive correlation of CD8 and FOXP3 staining with activin A at the protein level in both primary and metastatic epithelial ovarian cancer samples. Furthermore, Activin‐A (inhibin‐βA) is significantly elevated in EOC patient ascites. Conclusion INHBA expression is elevated within EOC, correlating with worse survival, with activin protein levels correlating with specific immune infiltration. Our findings suggest that activin‐A may play a role in suppressing anti‐tumor immunity in EOC, highlighting its potential as a therapeutic target.

Abstract Chimeric RNAs, distinct from DNA gene fusions, have emerged as promising therapeutic targets with diverse functions in cancer treatment. However, the functional significance and therapeutic potential of most chimeric RNAs remain unclear. Here we identify a novel fusion transcript of solute carrier family 2‐member 11 (SLC2A11) and macrophage migration inhibitory factor (MIF). In this study, we investigated the upregulation of SLC2A11–MIF in The Cancer Genome Atlas cohort and a cohort of patients from Sun Yat‐Sen Memorial Hospital. Subsequently, functional investigations demonstrated that SLC2A11–MIF enhanced the proliferation, antiapoptotic effects, and metastasis of bladder cancer cells in vitro and in vivo. Mechanistically, the fusion protein encoded by SLC2A11–MIF interacted with polypyrimidine tract binding protein 1 (PTBP1) and regulated the mRNA half‐lives of Polo Like Kinase 1, Roundabout guidance receptor 1, and phosphoinositide‐3‐kinase regulatory subunit 3 in BCa cells. Moreover, PTBP1 knockdown abolished the enhanced impact of SLC2A11–MIF on biological function and mRNA stability. Furthermore, the expression of SLC2A11–MIF mRNA is regulated by CCCTC‐binding factor and stabilized through RNA N4‐acetylcytidine modification facilitated by N‐acetyltransferase 10. Overall, our findings revealed a significant fusion protein orchestrated by the SLC2A11–MIF–PTBP1 axis that governs mRNA stability during the multistep progression of bladder cancer.

The important role of cholesterol in tumor metastasis has been widely studied in recent years. Ezetimibe is currently the only selective cholesterol uptake inhibitor on the market. Here, we explored the effect of ezetimibe on breast cancer metastasis by studying its impact on breast cancer cell migration, invasion, and epithelial‐mesenchymal transition (EMT). Differential gene expression analysis and validation were also carried out to compare ezetimibe‐treated and untreated breast cancer cells. Finally, breast cancer cells overexpressing TGFβ2 were constructed, and the effect of TGFβ2 on the migration and invasion of ezetimibe‐treated breast cancer cells was examined. Our results show that ezetimibe treatment of breast cancer cells inhibited cell migration, invasion, and EMT, and it significantly suppressed the expression of TGFβ2. Overexpression of TGFβ2 reversed the inhibitory effect of ezetimibe on the migration and invasion of breast cancer cells. Taken together, our results suggest that ezetimibe might be a potential candidate for the treatment of breast cancer metastasis.

Introduction Distant metastasis of T1a renal cell carcinoma is rare and whether metastasis is more probable in patients undergoing hemodialysis remains unclear. We report the autopsy case of a patient undergoing hemodialysis with multiple metastases that rapidly progressed from T1a renal cell carcinoma treated with multimodal therapy including nivolumab. Case presentation A 70‐year‐old male who underwent hemodialysis was diagnosed with clear cell carcinoma (pT1a, G2) after nephrectomy. Six months post‐surgery, bone and lung metastases appeared and treated with radiotherapy and pazopanib, respectively. Nivolumab was administered as second‐ and fourth‐line treatments for lung metastases. The patient died approximately 60 months after initial diagnosis; however, nivolumab controlled disease progression for 24 months. An autopsy revealed the lung's occupation with clear cell carcinoma tumor tissue. Conclusion Nivolumab has potential to control lung metastasis progression. Additionally, rechallenge is possible in patients with renal cell carcinoma undergoing hemodialysis.

Abstract Objectives We aim to assess the clinical value of 18F‐fluorodeoxyglucose positron (18F‐FDG‐PET) scan in detecting nodal and distant metastasis compared with computed tomography (CT) scan in patients with urothelial carcinoma or bladder cancer, aiming to improve staging accuracy and thereby better prognosticate and determine therapy. Methods A retrospective review of 75 patients with invasive bladder cancer (≥T1) who were staged with both CT and 18F‐FDG‐PET within an 8‐week interval was performed for the period between 2015 and 2020. Seventy‐two per cent (54/75) had formal pelvic lymph node (LN) dissection or biopsy of lesions suspicious for metastases. FDG‐PET definitions for positive sites were assessed depending on SUV Max (nodes with SUVmax >4 at any size, SUV > 2 for lymph nodes >8 mm, or any SUV if the lymph node was >10 mm on axial images). For CT scanning, enlarged LN by RECIST 1.1 criteria (>10 mm) as well as qualitative findings suggesting metastasis were considered positive. The analysis was based on the comparison of CT and 18F‐FDG‐PET findings to histopathology results from LN dissection or biopsies. Results Sensitivity, specificity, positive predictive values (PPV) and negative predictive value (NPV) of CT versus FDG‐PET for detecting metastasis, in patients who underwent pelvic LN dissection or biopsy of lesions suspicious of metastases, were 46.6% (95% CI: 21%–70%) versus 60% (95% CI: 32%–84%), 100% (95% CI: 91%–100%) versus 83.78% (95% CI: 69%–94%), 100% (95% CI: 63%–100%) versus 60% (95% CI: 32%–84%), and 82.2% (95% CI: 68%–92%) versus 83.78% (95% CI: 69%–94%), respectively. 7/75 (9.3%) patients avoided cystectomy due to 18F‐FDG‐PET features of metastases that were not detected by CT. Conclusion FDG‐PET may be more sensitive than CT for metastases in the staging of bladder cancer, which resulted in significant avoidance of aggressive local management in cases with occult metastasis.

Abstract Background Liver cancer is a malignancy with high morbidity and mortality rates. Serpin family E member 2 (SERPINE2) has been reported to play a key role in the metastasis of many tumors. In this study, we aimed to investigate the potential mechanism of SERPINE2 in liver cancer metastasis. Methods The Cancer Genome Atlas database (TCGA), including DNA methylation and transcriptome sequencing data, was utilized to identify the crucial oncogene associated with DNA methylation and cancer progression in liver cancer. Data from the TCGA and RNA sequencing for 94 pairs of liver cancer tissues were used to explore the correlation between SERPINE2 expression and clinical parameters of patients. DNA methylation sequencing was used to detect the DNA methylation levels in liver cancer tissues and cells. RNA sequencing, cytokine assays, immunoprecipitation (IP) and mass spectrometry (MS) assays, protein stability assays, and ubiquitination assays were performed to explore the regulatory mechanism of SERPINE2 in liver cancer metastasis. Patient‐derived xenografts and tumor organoid models were established to determine the role of SERPINE2 in the treatment of liver cancer using sorafenib. Results Based on the public database screening, SERPINE2 was identified as a tumor promoter regulated by DNA methylation. SERPINE2 expression was significantly higher in liver cancer tissues and was associated with the dismal prognosis in patients with liver cancer. SERPINE2 promoted liver cancer metastasis by enhancing cell pseudopodia formation, cell adhesion, cancer‐associated fibroblast activation, extracellular matrix remodeling, and angiogenesis. IP/MS assays confirmed that SERPINE2 activated epidermal growth factor receptor (EGFR) and its downstream signaling pathways by interacting with EGFR. Mechanistically, SERPINE2 inhibited EGFR ubiquitination and maintained its protein stability by competing with the E3 ubiquitin ligase, c‐Cbl. Additionally, EGFR was activated in liver cancer cells after sorafenib treatment, and SERPINE2 knockdown‐induced EGFR downregulation significantly enhanced the therapeutic efficacy of sorafenib against liver cancer. Furthermore, we found that SERPINE2 knockdown also had a sensitizing effect on lenvatinib treatment. Conclusions SERPINE2 promoted liver cancer metastasis by preventing EGFR degradation via c‐Cbl‐mediated ubiquitination, suggesting that inhibition of the SERPINE2‐EGFR axis may be a potential target for liver cancer treatment.

The initial excitement generated more than two decades ago by the discovery of drugs targeting fatty acid synthase (FASN)‐catalyzed de novo lipogenesis for cancer therapy was short‐lived. However, the advent of the first clinical‐grade FASN inhibitor (TVB‐2640; denifanstat), which is currently being studied in various phase II trials, and the exciting advances in understanding the FASN signalome are fueling a renewed interest in FASN‐targeted strategies for the treatment and prevention of cancer. Here, we provide a detailed overview of how FASN can drive phenotypic plasticity and cell fate decisions, mitochondrial regulation of cell death, immune escape and organ‐specific metastatic potential. We then present a variety of FASN‐targeted therapeutic approaches that address the major challenges facing FASN therapy. These include limitations of current FASN inhibitors and the lack of precision tools to maximize the therapeutic potential of FASN inhibitors in the clinic. Rethinking the role of FASN as a signal transducer in cancer pathogenesis may provide molecularly driven strategies to optimize FASN as a long‐awaited target for cancer therapeutics.

Abstract Background Current diagnostic tools are unable to distinguish low‐grade indolent prostate cancer (PrCa) from that with a propensity to become metastatic and/or lethal. Recent evidence suggests that reprogramming of the transcriptome may drive the metastatic phenotype, and that this reprogramming is controlled, at least in part, by epigenetic changes to the DNA of cancer cells, including methylation. These changes, referred to as ‘epigenetic drivers,’ have previously been associated with cancer cell survival. Methods Here, using Illumina Methylation EPIC array data of paired primary PrCa and metastatic bone samples, we identified WNT5A as a putative epi‐driver of PrCa metastasis to the bone, which was further validated in vitro. Results Significantly higher WNT5A methylation was observed in primary PrCa samples and 22Rv1 cells compared to metastatic bone samples and PC‐3 cells. This higher methylation was associated with significantly lower WNT5A gene expression. Conclusion Given the limited effective therapies available for metastatic cancer sufferers, particularly those whose disease has metastasised to the bone, WNT5A presents as a potential putative target for therapy.

Abstract Objective Breast cancer is one of the leading cancer causes among women worldwide. It can be classified as invasive ductal carcinoma (IDC) or metastatic cancer. Early detection of breast cancer is challenging due to the lack of early warning signs. Generally, a mammogram is recommended by specialists for screening. Existing approaches are not accurate enough for real‐time diagnostic applications and thus require better and smarter cancer diagnostic approaches. This study aims to develop a customized machine‐learning framework that will give more accurate predictions for IDC and metastasis cancer classification. Methods This work proposes a convolutional neural network (CNN) model for classifying IDC and metastatic breast cancer. The study utilized a large‐scale dataset of microscopic histopathological images to automatically perceive a hierarchical manner of learning and understanding. Results It is evident that using machine learning techniques significantly (15%–25%) boost the effectiveness of determining cancer vulnerability, malignancy, and demise. The results demonstrate an excellent performance ensuring an average of 95% accuracy in classifying metastatic cells against benign ones and 89% accuracy was obtained in terms of detecting IDC. Conclusions The results suggest that the proposed model improves classification accuracy. Therefore, it could be applied effectively in classifying IDC and metastatic cancer in comparison to other state‐of‐the‐art models.

ABSTRACT Lung squamous cell carcinoma (LUSC) is characterized by a high rate of metastasis and recurrence, leading to a poor prognosis for affected patients. Intestinal metastasis of LUSC is a rare clinical occurrence. Treatment options for LUSC patients with intestinal metastasis are limited, and no standard therapy guidelines exist for managing these cases. In this review, we discuss the clinical features, diagnosis, and treatment of LUSC patients with intestinal metastasis and present a rare case of LUSC with intestinal metastasis. We describe a patient who presented with a severe cough and chest pain and diagnosed with LUSC and bone tumor. Initially, the primary LUSC and bone tumor were controlled with standard treatments. However, the primary LUSC reoccurred shortly after treatment, this time with intestinal metastasis, for which effective treatments are lacking. Our observation from the case suggests that LUSC metastasizing to intestinal tract is associated with a poorer prognosis.

ABSTRACT Background Lung adenocarcinoma (LUAD) is a fatal disease with metabolic abnormalities. The dysregulation of S100 calcium‐binding protein A2 (S100A2), a member of the S100 protein family, is connected to the development of various cancers. The impact of S100A2 on the LUAD occurrence and metastasis, however, has not yet been reported. The functional mechanism of S100A2 on LUAD cell metastasis was examined in this article. Methods The expression of TFAP2A and S100A2 in LUAD tissues and cells was analyzed by bioinformatics and qRT‐PCR, respectively. The enrichment pathway analysis was performed on S100A2. Bioinformatics analysis determined the binding relationship between TFAP2A and S100A2, and their interaction was validated through dual‐luciferase and chromatin immunoprecipitation experiments. Cell viability was determined using cell counting kit‐8 (CCK‐8). A transwell assay was performed to analyze the invasion and migration of cells. Immunofluorescence was conducted to obtain vimentin and E‐cadherin expression, and a western blot was used to detect the expression of MMP‐2, MMP‐9, GLS, and GLUD1. The kits measured the NADPH/NADP ratio, glutathione (GSH)/glutathione disulfide (GSSG) levels, and the contents of glutamine, α‐KG, and glutamate. Results S100A2 was upregulated in LUAD tissues and cells, and S100A2 mediated glutamine metabolism to induce LUAD metastasis. Additionally, the transcriptional regulator TFAP2A was discovered upstream of S100A2, and TFAP2A expression was upregulated in LUAD, which indicated that TFAP2A promoted the S100A2 expression. The rescue experiment found that upregulation of S100A2 could reverse the inhibitory effects of silencing TFAP2A on glutamine metabolism and cell metastasis. Conclusion In conclusion, by regulating glutamine metabolism, the TFAP2A/S100A2 axis facilitated LUAD metastasis. This suggested that targeting S100A2 could be beneficial for LUAD treatment.

ABSTRACT Background Breast cancer is the most predominant and heterogeneous cancer in women. Moreover, breast cancer has a high prevalence to metastasize to distant organs, such as the brain, lungs, and bones. Patients with breast cancer metastasis to the bones have poor overall and relapse‐free survival. Moreover, treatment using chemotherapy and immunotherapy is ineffective in preventing or reducing cancer metastasis. Recent Findings Microorganisms residing in the gut and breast, termed as the resident microbiome, have a significant influence on the formation and progression of breast cancer. Recent studies have identified some microorganisms that induce breast cancer metastasis to the bone. These organisms utilize multiple mechanisms, including induction of epithelial–mesenchymal transition, steroid hormone metabolism, immune modification, bone remodeling, and secretion of microbial products that alter tumor microenvironment, and enhance propensity of breast cancer cells to metastasize. However, their involvement makes these microorganisms suitable as novel therapeutic targets. Thus, studies are underway to prevent and reduce breast cancer metastasis to distant organs, including the bone, using chemotherapeutic or immunotherapeutic drugs, along with probiotics, antibiotics or fecal microbiota transplantation. Conclusions The present review describes association of gut and breast microbiomes with bone metastases. We have elaborated on the mechanisms utilized by breast and gut microbiomes that induce breast cancer metastasis, especially to the bone. The review also highlights the current treatment options that may target both the microbiomes for preventing or reducing breast cancer metastases. Finally, we have specified the necessity of maintaining a diverse gut microbiome to prevent dysbiosis, which otherwise may induce breast carcinogenesis and metastasis especially to the bone. The review may facilitate more detailed investigations of the causal associations between these microbiomes and bone metastases. Moreover, the potential treatment options described in the review may promote discussions and research on the modes to improve survival of patients with breast cancer by targeting the gut and breast microbiomes.

ABSTRACT Background Integrin‐Binding Sialoprotein (IBSP) has been implicated in tumor progression across various cancers. However, the specific role of IBSP in breast cancer remains underexplored. There is a need to investigate the mechanisms by which IBSP influences breast cancer progression and its potential as a therapeutic target. Aims This study aims to elucidate the role of IBSP in breast cancer, particularly its impact on tumor progression and its relationship with prognosis. We also seek to understand the underlying mechanisms, including the involvement of the BMP‐SMAD signaling pathway, and to explore the potential of targeting IBSP for therapeutic interventions. Methods and Results Overexpression of IBSP in breast cancer cells led to increased migration and invasion, whereas IBSP interference reduced these behaviors, indicating its role in enhancing tumor progression. Differentially expressed genes were significantly enriched in the BMP‐SMAD signaling pathway, a critical pathway for osteogenic differentiation. Transcription Factor Binding: Dual luciferase reporter assays demonstrated that SMAD4 specifically binds to the IBSP promoter, establishing a regulatory link between SMAD4 and IBSP expression. Silencing IBSP (si‐IBSP) mitigated the effects of SMAD4‐induced tumor proliferation, confirming that IBSP acts as a downstream target of SMAD4 in the BMP signaling pathway. Conclusion Our study reveals that IBSP plays a significant role in breast cancer progression through the BMP‐SMAD4 signaling pathway. Targeting IBSP could be a promising therapeutic strategy for breast cancer treatment. Further research into IBSP inhibitors may offer new avenues for improving treatment outcomes and managing breast cancer more effectively.

Abstract Milk exosomes, extracellular nanovesicles that are naturally present in milk, have gained significant attention in cancer research for their potential to revolutionize cancer treatment strategies. They possess a specific set of characteristics that make them promising nanoscale vehicles for targeted drug delivery systems. Their inherent biocompatibility, coupled with their ability to effectively encapsulate and transport therapeutic agents directly into tumor cells, suggests the possibility of developing novel cancer therapies, potentially minimizing side effects associated with conventional therapies. However, recent studies have shown that milk exosomes have a dual nature, which is not entirely positive. Although they show potential in delivering anticancer therapeutics, evidence suggests they may also, under certain conditions, contribute to cancer progression. This paradoxical nature necessitates a better understanding of how they interact and work in different stages of cancer. Further investigation is crucial to understand the factors influencing their behaviour and to develop strategies that can maximize their therapeutic prospects while mitigating potential risks associated with their use in cancer treatment.

Abstract Exosomes are nano‐scale vesicles involved in intercellular communication and have a significant role in cancer progression. Tetraspanins, are transmembrane proteins enriched in exosomes. These proteins have significant role in exosome biogenesis, cargo sorting,and target‐cell interactions, influencing tumor development and therapeutic response. Exosomal tetraspanins, including CD9, CD63, CD81, and Tspan8, contribute to tumor cell proliferation, angiogenesis, extracellular matrix remodelling, immune evasion, and promote metastasis. Their ability to prepare distant organ sites for colonization highlights their role in establishing the premetastatic niche. Expression profiling of exosomal tetraspanin proteins in cancer become a promising diagnostic and prognostic biomarker. Exosomal tetraspanin proteins also be an effective therapeutic target in cancer.This article highlighted impactful role ofexosomal tetraspanin Proteins in Cancer.

Abstract Metastasis is a major contributing factor that affects the prognosis of melanoma patients. Nevertheless, the underlying molecular mechanisms involved in melanoma metastasis are not yet entirely understood. Here, we identified ubiquitin‐specific protease 22 (USP22) as a pro‐oncogenic protein in melanoma through screening the survival profiles of 52 ubiquitin‐specific proteases (USPs). USP22 demonstrates a strong association with poor clinical outcomes and is significantly overexpressed in melanoma. Ablation of USP22 expression remarkably attenuates melanoma migration, invasion, and epithelial–mesenchymal transition in vitro and suppresses melanoma metastasis in vivo. Mechanistically, USP22 controls melanoma metastasis through the SIRT1/PTEN/PI3K pathway. In addition, we conducted an United States Food and Drug Administration‐approved drug library screening and identified topotecan as a clinically applicable USP22‐targeting molecule by promoting proteasomal degradation of USP22. Finally, we found that both pharmacological and genetic silence of USP22 sensitize RSL3‐induced ferroptosis through suppressing the PI3K/Akt/mTOR pathway and its downstream SCD, and ferroptosis inhibitor could partly rescued the decreased lung metastasis by topotecan in vivo. Overall, our findings reveal a prometastatic role of USP22 and identify topotecan as a potent USP22‐targeting drug to limit melanoma metastasis.

Abstract Cancer metastasis is the leading cause of mortality in patients with hepatocellular carcinoma (HCC). To meet the rapid malignant growth and transformation, tumor cells dramatically increase the consumption of nutrients, such as amino acids. Peptide transporter 1 (PEPT1), a key transporter for small peptides, has been found to be an effective and energy‐saving intracellular source of amino acids that are required for the growth of tumor cells. Here, the role of PEPT1 in HCC metastasis and its underlying mechanisms is explored. PEPT1 is upregulated in HCC cells and tissues, and high PEPT1 expression is associated with poor prognosis in patients with HCC. PEPT1 overexpression dramatically promoted HCC cell migration, invasion, and lung metastasis, whereas its knockdown abolished these effects both in vitro and in vivo. Mechanistic analysis revealed that high PEPT1 expression increased cellular dipeptides in HCC cells that are responsible for activating the MAP4K4/G3BP2 signaling pathway, ultimately facilitating the phosphorylation of G3BP2 at Thr227 and enhancing HCC metastasis. Taken together, these findings suggest that PEPT1 acts as an oncogene in promoting HCC metastasis through dipeptide‐induced MAP4K4/G3BP2 signaling and that the PEPT1/MAP4K4/G3BP2 axis can serve as a promising therapeutic target for metastatic HCC.

Key message The visualization of black pigment during EBUS‐TBNA suggests a relapse of melanoma. This case highlights the value of EBUS‐TBNA in diagnosing metastatic melanoma, particularly when the macroscopic appearance of the aspirate suggests the diagnosis.

Key message The differential diagnosis of a lung mass with multiple pulmonary nodules includes metastases of lung cancer, mycobacterial infections, and pulmonary mycosis. Pulmonary cryptococcosis should be recognized, especially in immunocompromised patients.

Abstract Background Renal cell carcinoma (RCC) is one of the most common and prevalent cancers all around the world with a prevalence of 3%. Approximately twenty percent of patients present with metastasis at the time of diagnosis, while late metastasis in renal cell carcinoma is a quite familiar phenomenon. Head and neck and particularly thyroid metastasis from RCC are rare events. Case We present a case of a 75‐year‐old woman who developed thyroid nodules 13 years after nephrectomy for RCC. Diagnosis confirmed metastatic RCC through clinical history, histomorphology, and immunohistochemistry. Imaging studies revealed thyroid lesions without metastasis in other organs. The patient underwent total thyroidectomy and remains symptom‐free after 2 years of follow‐up. Conclusion This case highlights the importance of considering metastatic lesions is crucial in managing thyroid nodules in patients with a history of cancer, particularly RCC.

Abstract In recent decades, the role of tumor biomechanics on cancer cell behavior at the primary site has been increasingly appreciated. However, the effect of primary tumor biomechanics on the latter stages of the metastatic cascade, such as metastatic seeding of secondary sites and outgrowth remains underappreciated. This work sought to address this in the context of triple negative breast cancer (TNBC), a cancer type known to aggressively disseminate at all stages of disease progression. Using mechanically tuneable model systems, mimicking the range of stiffness's typically found within breast tumors, it is found that, contrary to expectations, cancer cells exposed to softer microenvironments are more able to colonize secondary tissues. It is shown that heightened cell survival is driven by enhanced metabolism of fatty acids within TNBC cells exposed to softer microenvironments. It is demonstrated that uncoupling cellular mechanosensing through integrin β1 blocking antibody effectively causes stiff primed TNBC cells to behave like their soft counterparts, both in vitro and in vivo. This work is the first to show that softer tumor microenvironments may be contributing to changes in disease outcome by imprinting on TNBC cells a greater metabolic flexibility and conferring discrete cell survival advantages.

Abstract Background The combination of dual‐targeted human epidermal growth factor receptor 2 (HER2) therapy and chemotherapy is the standard first‐line regimen for recurrent/metastatic breast cancer (mBC). However, the toxicity of such combination therapy can lead to some patients being unable to tolerate adverse events or bear treatment costs. As a novel irreversible pan‐ErbB receptor TKI (pyrotinib), can the dual oral administration of pyrotinib plus capetabine (PyroC) provide first‐line survival benefits and serve as a more affordable treatment option? Methods This real‐world retrospective study included patients diagnosed with HER2‐positive mBC who received PyroC as a first‐line treatment at West China Hospital between May 2018 and July 2023. The survival data and toxicity profiles were reported in this study. Results A total of 64 patients received PyroC as first‐line therapy. The median progression‐free survival (PFS) was 19.6 months (95% CI 15.0–27.2), while overall survival (OS) has not yet been reached. Kaplan–Meier analysis indicated that age (≥60, p = 0.03) and metastasis sites (p = 0.004) were related to poor efficacy of PyroC, while there was no relationship between effectiveness and menstrual status, hormone receptor (HR) status or previous treatment with anti‐HER2 therapy. Furthermore, the objective response rate (ORR) and disease control rate (DCR) were 79.7% and 98.4%, respectively. Of the patients, 78.1% reported treatment‐related adverse events (TRAEs). The predominant adverse events were diarrhea (n = 46, 71.9%) and hand‐foot syndrome (n = 10, 15.6%). Conclusion The dual oral administration regimen (PyroC) has a promising ORR or PFS in HER2‐positive mBC patients, with an acceptable safety profile and convenience.

Abstract Background We previously reported that metastases are generally characterized by a core program of gene expression that activates tissue remodeling/vascularization, alters ion homeostasis, induces the oxidative metabolism, and silences extracellular matrix interactions. This core program distinguishes metastases from their originating primary tumors as well as from their destination host tissues. Therefore, the gene products involved are potential targets for anti‐metastasis drug treatment. Methods Because the silencing of extracellular matrix interactions predisposes to anoiks in the absence of active survival mechanisms, we tested inhibitors against the other three components. Results Individually, the low‐specificity VEGFR blocker pazopanib (in vivo combined with marimastat), the antioxidant dimethyl sulfoxide (or the substitute atovaquone, which is approved for internal administration), and the ionic modulators bumetanide and tetrathiomolybdate inhibited soft agar colony formation by breast and pancreatic cancer cell lines. The individual candidate agents have a record of use in humans (with limited efficacy when administered individually) and are available for repurposing. In combination, the effects of these drugs were additive or synergistic. In two mouse models of cancer (utilizing 4T1 cells or B16‐F10 cells), the combination treatment with these medications, applied immediately (to prevent metastasis formation) or after a delay (to suppress established metastases), dramatically reduced the occurrence of disseminated foci. Conclusions The combination of tissue remodeling inhibitors, suppressors of the oxidative metabolism, and ion homeostasis modulators has very strong promise for the treatment of metastases by multiple cancers.

Abstract Cancer is a disease with molecular heterogeneity that is closely related to gene mutations and epigenetic changes. The principal histological subtype of lung cancer is non‐small cell lung cancer (NSCLC). Long noncoding RNA (lncRNA) is a kind of RNA that is without protein coding function, playing a critical role in the progression of cancer. In this research, the regulatory mechanisms of lncRNA phosphorylase kinase regulatory subunit alpha 1 antisense RNA 1 (PHKA1‐AS1) in the progression of NSCLC were explored. The increased level of N6‐methyladenosine (m6A) modification in NSCLC caused the high expression of PHKA1‐AS1. Subsequently, high‐expressed PHKA1‐AS1 significantly facilitated the proliferation and metastasis of NSCLC cells, and these effects could be reversed upon the inhibition of PHKA1‐AS1 expression, both in vivo and in vitro. Additionally, the target protein of PHKA1‐AS1 was actinin alpha 4 (ACTN4), which is known as an oncogene. Herein, PHKA1‐AS1 could enhance the protein stability of ACTN4 by inhibiting its ubiquitination degradation process, thus exerting the function of ACTN4 in promoting the progress of NSCLC. In conclusion, this research provided a theoretical basis for further exploring the potential mechanism of NSCLC metastasis and searching novel biomarkers related to the pathogenesis and progression of NSCLC.

Abstract Antibodies to programmed cell death protein 1 (anti‐PD‐1) have become a promising immunotherapy for triple negative breast cancer (TNBC), blocking PD‐L1 signaling from pro‐tumor cells through T cell PD‐1 receptor binding. Nevertheless, only 10%–20% of PD‐L1+ metastatic TNBC patients who meet criteria benefit from immune checkpoint blockade (ICB), and biomarkers to predict patient response have been elusive. We have previously developed an immunological niche, consisting of a microporous implant in the subcutaneous space, that supports tissue formation whose immune composition is consistent with that within vital organs. Herein, we investigated dynamic gene expression within this immunological niche to provide biomarkers of response to anti‐PD‐1. In a 4T1 model of metastatic TNBC, we observed sensitivity and resistance to anti‐PD‐1 based on primary tumor growth and survival. The niche was biopsied before, during, and after anti‐PD‐1 therapy, and analyzed for cell types and gene expression indicative of treatment refractivity. Myeloid cell‐to‐lymphocyte ratios were altered between ICB‐sensitivity and resistance. Longitudinal analysis of gene expression implicated dynamic myeloid cell function that stratified sensitivity from resistance. A niche‐derived gene signature predicted sensitivity or resistance prior to therapy. Analysis of the niche to monitor immunotherapy response presents a new opportunity to personalize care and investigate mechanisms underlying treatment resistance. Summary: A remote implant identified biomarkers that predict anti‐PD‐1 response before therapy, providing a unique tool to understand heterologous immunotherapy resistance in triple negative breast cancer.

Abstract Intercellular communication often relies on exosomes as messengers and is critical for cancer metastasis in hypoxic tumor microenvironment. Some circular RNAs (circRNAs) are enriched in cancer cell‐derived exosomes, but little is known about their ability to regulate intercellular communication and cancer metastasis. Here, by systematically analyzing exosomes secreted by non‐small cell lung cancer (NSCLC) cells, a hypoxia‐induced exosomal circPLEKHM1 is identified that drives NSCLC metastasis through polarizing macrophages toward to M2 type. Mechanistically, exosomal circPLEKHM1 promoted PABPC1‐eIF4G interaction to facilitate the translation of the oncostatin M receptor (OSMR), thereby promoting macrophage polarization for cancer metastasis. Importantly, circPLEKHM1‐targeted therapy significantly reduces NSCLC metastasis in vivo. circPLEKHM1 serves as a prognostic biomarker for metastasis and poor survival in NSCLC patients. This study unveils a new circRNA‐mediated mechanism underlying how cancer cells crosstalk with macrophages within the hypoxic tumor microenvironment to promote metastasis, highlighting the importance of exosomal circPLEKHM1 as a prognostic biomarker and therapeutic target for lung cancer metastasis.

Aldehyde dehydrogenase 1A3 (ALDH1A3) is a cancer stem cell marker that promotes metastasis. Triple‐negative breast cancer (TNBC) progression has been linked to ALDH1A3‐induced gene expression changes. To investigate the mechanism of ALDH1A3‐mediated breast cancer metastasis, we assessed the effect of ALDH1A3 on the expression of proteases and the regulators of proteases that degrade the extracellular matrix, a process that is essential for invasion and metastasis. This revealed that ALDH1A3 regulates the plasminogen activation pathway; it increased the levels and activity of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA). This resulted in a corresponding increase in the activity of serine protease plasmin, the enzymatic product of tPA and uPA. The ALDH1A3 product all‐trans‐retinoic acid similarly increased tPA and plasmin activity. The increased invasion of TNBC cells by ALDH1A3 was plasminogen‐dependent. In patient tumours, ALDH1A3 and tPA are co‐expressed and their combined expression correlated with the TNBC subtype, high tumour grade and recurrent metastatic disease. Knockdown of tPA in TNBC cells inhibited plasmin generation and lymph node metastasis. These results identify the ALDH1A3–tPA–plasmin axis as a key contributor to breast cancer progression.

High‐grade serous ovarian cancer (HGSOC) is the deadliest gynecological malignancy. The most common form of metastatic spread of HGSOC is transcoelomic dissemination. In this process, detached cells from the primary tumor aggregate as tumorspheres and promote the accumulation of peritoneal ascites. This represents an early event in HGSOC development and is indicative of poor prognosis. In this study, based on tumorspheres isolated from ascitic liquid samples from HGSOC patients, ovarian cancer spheroid 3D cultures, and in vivo models, we describe a key signal for tumorsphere formation in HGSOC. We report that platelet‐derived growth factor receptor beta (PDGFRβ) is essential for fibronectin‐mediated cell clustering of ovarian cancer cells into tumorspheres. This effect is mediated by the kinase NUAK family SNF1‐like kinase 1 (NUAK1) and blocked by PDGFRβ pharmacological or genetic inhibition. In the absence of PDGFRβ, ovarian cancer cells can be provided with fibronectin by cancer‐associated fibroblasts to generate chimeric spheroids. This work provides new insights that uncover potential targets to prevent peritoneal dissemination, the main cause of advanced disease in HGSOC patients.

Hematogenous metastasis limits the survival of colorectal cancer (CRC) patients. Here, we illuminated the roles of CD44 isoforms in this process. Isoforms 3 and 4 were predominantly expressed in CRC patients. CD44 isoform 4 indicated poor outcome and correlated with epithelial–mesenchymal transition (EMT) and decreased oxidative phosphorylation (OxPhos) in patients; opposite associations were found for isoform 3. Pan‐CD44 knockdown (kd) independently impaired primary tumor formation and abrogated distant metastasis in CRC xenografts. The xenograft tumors mainly expressed the clinically relevant CD44 isoforms 3 and 4. Both isoforms were enhanced in the paranecrotic, hypoxic tumor regions but were generally absent in lung metastases. Upon CD44 kd, tumor angiogenesis was increased in the paranecrotic areas, accompanied by reduced hypoxia‐inducible factor‐1α and CEACAM5 but increased E‐cadherin expression. Mitochondrial genes and proteins were induced upon pan‐CD44 kd, as were OxPhos genes. Hypoxia increased VEGF release from tumor spheres, particularly upon CD44 kd. Genes affected upon CD44 kd in xenografts specifically overlapped concordantly with genes correlating with CD44 isoform 4 (but not isoform 3) in patients, validating the clinical relevance of the used model and highlighting the metastasis‐promoting role of CD44 isoform 4.